N-Acetyl Cysteine (NAC)

N-Acetyl Cysteine (NAC) is a prodrug for L-cysteine, a precursor to the antioxidant glutathione, an essential antioxidant in the body. NAC supports glutathione replenishment which has been found to bind to the glutamate recognition sites of the NMDA and AMPA receptors. It also promotes healthy inflammatory responses.

Overview

What is N-Acetyl Cysteine?

N-Acetyl Cysteine (also known as Acetylcysteine or NAC) is a prodrug for L-cysteine, a precursor to the antioxidant glutathione, an essential antioxidant in the body. NAC supports glutathione replenishment which has been found to bind to the glutamate recognition sites of the NMDA and AMPA receptors. It also promotes healthy inflammatory responses. Acetylcysteine was initially patented in 1960 and licensed for use in 1968. It is on the World Health Organization's List of Essential Medicines and is easily accessible for a very affordable price.

“Acetylcysteine, also known as N-acetylcysteine, is a medication that is used to treat paracetamol overdose, and to loosen thick mucus in individuals with cystic fibrosis or chronic obstructive pulmonary disease. It can be taken intravenously, by mouth, or inhaled as a mist. Some people use it as a dietary supplement.”

Improves Cognitive Function

Combinations of NAC with other antioxidants improve cognition in both healthy older people and those with mild cognitive impairment. (R) (R)

NAC has many studies on enhancing cognitive function in Alzheimer’s, Parkinson’s, and schizophrenia. Currently, it’s under research for boosting cognitive performance after general anesthesia. (R)

Reduces Symptoms of Depression

NAC helps people with depression by balancing glutamate levels within the brain. Doing so, it reduces inflammation and increases the growth of new brain cells. R

In a study of more than 500 participants, NAC shows an improvement in symptoms of depression and overall functionality. At 2000mg per day, it improves mood in people diagnosed with depression. (R), (R)

Helps Symptoms of Bipolar Disorder and Mania

NAC improves chronic health issues such as heart disease and hormonal imbalance in people with Bipolar Disorder. In a 6-month study, NAC indirectly shows to affect overall health, antioxidant and inflammation levels, as well as mood. (R)

Another study on 17 subjects with bipolar disorder, NAC shows improvements in low moods and reduction in overall associating symptoms after six months of supplementation. (R)

In a study of 15 individuals suffering from mania, NAC also shows improvement after a six-month regime. The group receiving NAC had a reduction in symptoms versus the one receiving placebo. However, mood swings seem to worsen as a result. (R)

Reduces Symptoms of OCD (Obsessive Compulsive Disorder)

NAC balances glutamate levels as well as increases antioxidants within the brain. In a study of 44 subjects with OCD, a NAC dose of 2000mg added to standard medication shows to improve symptoms, even in severe cases. R

Another study of 48 subjects who didn't respond to typical treatment, NAC shows to improve symptoms after a 3-month period safely. (R)

NAC is useful for obsessive-compulsive disorders according to extensive research. It shows promising benefits and has very few side-effects. (R)

Improves Male Fertility

In addition to helping women with PCOS (Polycystic ovary syndrome), NAC may help increase fertility in men. Oxidative stress damages the sperm’s DNA, which results in reducing fertility. (R)

A study done on 120 infertile men receiving NAC, improvements were notable in semen quality and antioxidant status after a period of three months. (R)

Other studies look at the fertility benefits of NAC in combination with other antioxidants such as B vitamins, vitamin C and D. The combination improves the sperm count in those with low sperm count. (R)

In an extensive study of almost 500 infertile men, NAC with selenium show improvement in fertility after a six month period. (R)

Sub-fertility Conditions

Some men are sub-fertile — they are less fertile without an apparent reason. In 84 of subfertile men trying to conceive, NAC combination supplement called Condensyl (with vitamins, zinc, fig extract, and vitamin E) increased pregnancy rates. It raises the “fertility potential” of subfertile men increasing the rate of successful pregnancy. (R)

The typical NAC dose for improving fertility in those studies was 600 mg/day.

Boosts Skin Health

Interestingly, NAC can be used as a cream or gel to improve skin health. It boosts glutathione in the skin protecting it from damage. Furthermore, NAC reduces skin inflammation and normalizes skin cell division. It’s used for eczema, skin irritation, radiation-induced skin damage, wound healing, and acne. In a study of 100 participants, a 5% NAC gel shows to reduce mild to moderate acne. (R)

Overall, NAC skin formulations are promising and very safe. Case reports and animal studies support this wide range of skin benefits of NAC.

May Improve Autism

NAC seems to benefit children with autism. In a study of 33 autistic children, NAC (900-2,700 mg/day) shows to reduce irritability after three months period. (R)

In 2 different studies with 80 autistic children, those receiving NAC as an add-on to their medication (risperidone) show less irritability and hyperactivity after two months period. (R), (R)

Reduces Muscle Fatigue

Overall, NAC tends to help muscles improve blood flow during intense training as well as recover faster after a workout.

It also seems to help older individuals in improving fitness and enhancing endurance in athletes on the short-term. However, long-term NAC with exercise may prevent muscle recovery.

NAC also protects the liver from the harmful effects of anti-tuberculosis drugs as shown in a study of 60 participants. Those receiving NAC show intact liver after treatment, while 40% of those who didn’t take NAC suffer liver damage. (R)

Reliefs ADHD Symptoms

In a study of nearly 100 ADHD participants, NAC shows to reduce ADHD symptoms in patients with as well as improving cognition, impulsivity, and overall symptoms.

Dosage

How To Take N-Acetyl Cysteine?

The typical dose for general wellness and gut health is 500mg per day taken in the morning on an empty stomach 800to2,400mg are the most common across clinical studies. However, for a chronic health condition, consider a higher dose. Studies concerning addiction and mental health issues use doses closer to 3000 mg/day.

Side Effects

What Are N-Acetyl Cysteine Side Effects?

N-Acetyl Cysteine is a safe substance with very few known side effects. Although occasionally, it can cause nausea, diarrhea, or constipation.

Large doses in a mouse model showed that acetylcysteine could potentially cause damage to the heart and lungs. They found that acetylcysteine was metabolized to S-nitroso-N acetylcysteine (SNOAC), which increased blood pressure in the lungs and right ventricle of the heart (pulmonary artery hypertension) in mice treated with acetylcysteine.

The effect was similar to that observed following a 3-week exposure to an oxygen-deprived environment (chronic hypoxia).

The authors also found that SNOAC induced a hypoxia-like response in the expression of several important genes both in vitro and in vivo.

User Experience

Nootropics Depot

NAC is the supplement of choice for helping to mitigate nasal congestion. I've found even with a cold, taking a large dose divided up into several small doses separated by 2-4 hours throughout the day significantly controls the nose situation. Recently while going through this routine, I also noticed heightened mental clarity which quickly was attributed to the NAC as nothing else in my regular stack had changed. Combined with the fact the loose powder is inexpensive, NAC has high opinion from me. Con, it tastes terrible. It seriously tastes like butt if that was made from rubber. Capsulating it yourself is highly recommended!

Nootropics Depot II

NAC is an essential part of my daily routine. I take 2000mg every morning and if I feel a cold coming on I also take 1000 or 2000mg of an evening. Every winter I get a cold which precipitates a severe chest infection. It is now halfway through winter and I have not yet even caught a cold, despite the fact that the rest of my family has been sick with colds. My nose usually runs all winter but the mucous dissolving properties of NAC somehow even ameliorate that. I use Nootropics Depot's NAC because I know it's pure and independently tested. It comes in user friendly packaging, it's inexpensive, the postage is tracked and it arrives quickly.

Frequently Asked Questions

N Acetyl L Cysteine, also known as N Acetyl Cysteine or NAC, is an acetylated form of L Cysteine. NAC is one of few natural mucolytic agents. Mucolytic agents help thin out mucus which makes it easier to cough up mucus. NAC is also used to enhance the production of glutathione when it is normally depleted. Glutathione benefits are plentiful and thus, supplementing with NAC can provide many of the glutathione benefits we would see with glutathione supplementation.

Studies observing glutathione levels after taking a NAC supplement found that NAC elevated glutathione levels. This is significant because the supplementation of glutathione on its own did not significantly increase glutathione levels. Since NAC is able to increase glutathione, NAC benefits have been linked to skin health, organ health, and promoting vitality. Additionally, taking a NAC supplement is believed to have some detoxification effects since it allows more glutathione to be produced. In addition, NAC benefits include organ protective properties when exposed to alcohol. A study on rats found that a NAC supplement taken 30 min before alcohol exposure seemed to produce a protective effect while administration 4 hrs after alcohol exposure elevated organ tissue damage. Additionally, these protective behaviors increased when alcohol consumption was stopped. Additional trials confirmed that the protective properties NAC has against alcohol only work when taken prior to alcohol consumption. Again, it is important to note that NAC should only be taken prior to consumption of moderate quantities of alcoholic drinks. NAC should never be taken after the consumption of alcoholic drinks as it may have an opposite and detrimental effect on the liver. This is important to note as many hangover supplements, intended to be taken after the consumption of alcoholic drinks, contain N Acetyl L Cysteine. The cystine-glutamate antiporter on astrocytes is known to regulate synaptic levels of glutamate by taking up cystine, the oxidized dimer form of Cysteine, in exchange for glutamate release. It is believed that additional Cysteine through N Acetyl L Cysteine supplementation may provide more substrate to further reduce glutaminergic stimulation. This is important, as glutamate can over-excite neurons, which can cause neuronal damage. This is part of the reason why some people avoid the consumption of monosodium glutamate, which is more commonly known as MSG. It is falsely believed that the consumption of MSG will result in too much glutamate in the brain, which could then cause neurotoxic effects. The claims that MSG has negative effects in the brain have long been disproven, however, glutamate levels may increase independently from MSG consumption. It is believed that higher Cysteine levels in the brain may lower glutaminergic transmission by lowering the amount of glutamate release. It has been found that glutamate levels can be reduced within 1 hour of orally administering a NAC supplement, making NAC a great neuroprotective agent. Other N Acetyl L Cysteine uses were studied after the relationship between glutathione and NAC supplementation were established. Researchers were interested in NAC for its vitality enhancing effects. Studies on sprint performance found vitality enhancing effect when subjects used a NAC supplement but only a slight increase in vitality from baseline was achieved with a large dose.

The body converts N Acetyl L Cysteine which converts into Cysteine which is then converted to glutathione. Cysteine is an amino acid produced by the body but it requires methionine to do so. Cysteine is primarily found in animal proteins such as chicken, pork, sausage, turkey, fish and duck. Dairy sources of cysteine include yogurt, ricotta cheese, eggs, and cottage cheese. Cysteine is also found in some plant sources for vegetarians and vegans. Foods such as broccoli, red pepper, onion, granola and oat flakes are all good sources of Cysteine. Other sources include garlic, bananas, linseed, soy beans, and wheat germ. Low levels of Cysteine can delay growth in children and lower immunity. Weakness and muscle loss may also occur as a result of a low Cysteine die